From the Division of Occupational and Environmental Medicine (Drs MacIsaac
Blanc, and Janssen), Department of Medicine, and Department of Laboratory Medicine (Dr Gerona and Mr Friesen), University of California, San Francisco; Natural Resources Defense Council (Drs MacIsaac and Janssen), New York, NY; and Kaiser Permanente Medical Center (Drs Apatira, Coppolino, and Janssen), San Francisco, Calif.